Yukawa Unification in an SO(10) SUSY GUT: SUSY on the Edge

In this paper we analyze Yukawa unification in a three family SO(10) SUSY GUT. We perform a global $\chi^2$ analysis and show that SUSY effects do not decouple even though the universal scalar mass parameter at the GUT scale, $m_16$, is found to lie between 15 and 30 TeV with the best fit given for $m_{16}\approx25\,\text{TeV}$. Note, SUSY effects don’t decouple since stops and bottoms have mass of order $5\,\text{TeV}$, due to renormalization group running from $M_\text{GUT}$. The model has many testable predictions. Gauginos are the lightest sparticles and the light Higgs boson is very much Standard Model-like. The model is consistent with flavor and CP observables with the $\text{BR}(\mu\to e\gamma)$ close to the experimental upper bound. With such a large value of $m_{16}$ we clearly cannot be considered “natural” SUSY nor are we “Split” SUSY. We are thus in the region in between or “SUSY on the Edge.”